roundman

it's normal for the pressure to fall back like that if you don't start the car!!! remember I said the ECU shuts off the fuel pump after the key is turned on if it doesn't see the engine running after a second or two? this is what you are seeing so it's normal. the 42 psi with only the pump running and not the engine is without any engine vacuum to cause the pressure regulator to reduce the pressure, so this is the most pressure the pump can put out. the pump's flow rating is given at 45 psi in the manuals, so you might consider 42 a hair on the low side if it is truly the max the pump puts out. how accurate is the gauge you are using to check the fuel pressure????

grabbem88

so what should the max be for a 190lph pump?
it's a summit that is installed on my car,but the ford shop had the same reading.
i guess it wouldn't hurt to get a second opinion.before i start dropping the tank.

roundman

best thing I can say is contact the tech guys at Summit and ask them what the max pressure rating on that pump is, I'm sure they could tell you. and a second opinion is a good idea before messing with dropping the tank and all that's involved with doing that for sure! did you check the entire length of all your fuel lines to make sure none of them is kinked or partially mashed flat which would reduce the effective pressure reaching the injectors?? just another thing you might want to take a good look at too.

grabbem88

i will once,i have some time...it has been sitting for months now so i'm not hurting anything.
one more question does it make more since,now that when they are plugged in it acts
than when they are unhooked (safe mode) it runs ok????
this all happened when my starter went ape ****.....kept cranking till the battery went dead
i wonder if that caused my pump to short out or something?

vfast

I want to say 70 psi

grabbem88

for the fuel pump?right.

grabbem88

well i'm dropping the tank......i put a fuel gauge on,and taped it to my windsheild,and sure enough it dropped.

grabbem88

ok it's dropped........line looked good no cracks or kinks.
the pump is a walbro so did i get a bad one or what?
one more question i put it to my battery,and it ran,but i was expecting it to take off like an rc motor.
is there anything else to look for?